Most introductory botany courses teach us that conifers are wind pollinated and that wind pollination is facilitated, in this case, by the wings (sacci) on the pollen grains. A survey of pollination across the families of conifers reveals, however, a diverse array of mechanisms for pollen capture and delivery of male gametes to the ovule. Four of the five categories of conifer pollination mechanism that have been identified are facilitated by liquid, either in the form of a secretion from the ovule or as rainwater. In a few families of conifers, pollen is captured in a droplet secreted from an upwardly opening ovule and sinks into the pollen chamber. In all other families, ovules open downwardly at pollination. Commonly, pollen are captured on sticky surfaces near the opening of the ovule. The real function of sacci comes into play in some families when pollen float up into the ovule after the pollination drop is secreted from the micropyle; they are floatation devices. A third mechanism involves the engulfment of trapped pollen by growth of the micropyle prior to pollen germination in a secreted droplet within the micropyle. Finally, some members of Pinaceae and the Araucariaceae exhibit extended siphonogamy, after pollen is captured at a distance from the micropyle. This is analogous to the growth of long pollen tubes through stylar tissue in the angiosperms. Production of secreted pollination drops and evolution of extended siphonogamy are examples of adaptations that have allowed conifers to move beyond a dependence on water supplied by the environment for male gamete movement to the megagametophyte. I will illustrate the adaptations that have allowed conifers to radiate into relatively arid regions while maintaining efficient pollination over great distances and desiccation protection for germinating pollen.

Key words: conifer, gamete, ovule, pollen, pollination, sacci